<?php
/**
 * Created by PhpStorm.
 * User: User
 * Date: 2017/9/18
 * Time: 19:10
 */
echo '<table border="1">';
for($i=0;$i<100;$i++)
{
    $red=null;
   if(($i/10)%2) {
    $red = 'style="background-color:red"';

}
    if($i%10==0){
        echo '<tr'.$red.'>';
    }
    echo '<td >'.$i.'</td>';
    if($i%10==9){
        echo '</tr>';
    }
}
echo '</table>';
?>